Self-winding electric clock



(No Model.)

0. MI. CROOK'.

SELF WINDING ELECTRIC CLOCK.

No. 550,822. Patented 1390.6, 1895.

UNITED STATES PATENT OFFICE.

CHARLES M. CROOK, OF CHICAGO, ILLINOIS.

SELF-WINDING ELECTRIC CLOCK.

SPECIFICATION forming part of Letters Patent N 0. 550,822, dated December 3, 1895. A li ati fi1 dMarcl126, 1895. Serial No. 543,083. (No model.)

T 60% whom it may concern.-

Ee it known that 1, CHARLES M. CROOK, a citizen of the United States, residing at Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Electric Clocks, which are fully set forth in the following specification, reference being had to the accompanying drawings, forming a part thereof.

This invention is an improvement in clocks which are wound periodically at short in tervals by means of the energy imparted by an electric current through an electromagnet, the movement of the clock comprising contact making and breaking devices in the electric circuit, which determine the periodicity of the winding action.

These improvements consist, first, in an improved mechanism for transmitting the armatures movement to the winding devices, and, second, an improved contact making and breaking device.

In the drawings, Figure 1 is a side elevation of a portion of a clock-movement comprising my improvements. Fig. 2 is a front elevation, a portion of the forward frameplate and portions of other parts in the rear thereof being broken away to disclose parts still farther rearward. Fig. 3 is a detail section of Fig. 1, showing in side elevation the armature and its connection with the winding-drum, shaft, orbarrel, the armature being shown at its most proximate position to the magnet-poles, as at the instant in finishing the winding impulse. Fig. 4 is a similar detail elevation, section being taken behind the winding-sheave, which is therefore shown in dotted line, showing the armature most remote from the magnet-poles, as at the instant preceding the winding impulse. In this figure the portion of the spiral drum over which the band from the armaturedever passes is broken away to disclose parts in the rear thereof. Fig. 5 is a rear elevation of the contact making and breaking wheel, the shaft being shown in section. Fig. 6 is a detail rear elevation showing the adjustable fastenings which secure the insulating-block of the contact-making spring to the frame. Fig. 7

is an enlarged detail perspective of an automatic rotary contact making and breaking switch.

A is the prime wheel of the clock-train, mounted on the main shaft a.

Bis the mainspring,having one end fastened to the post b, and extending thence in successive coils around the drum A on the main shaft.

A is a ratchet-wheel rigid with the drum, and A is a pawl fulcrumed on the prime wheel A and engaging the ratchet-wheel, a being its spring. 7

C C C C are other wheels of the train, their particular construction and relation being of no specific importance in connection with my improvements.

D D are electromagnets of usual form and construction, the circuit-wire connecting at d to the frame and at d to the binding-post D, mounted in an insulating-block D which is mounted 011 the frame.

E is the armature, which is carried on the short arm or near the fulcrum e of the lever E, whose long arm E extends up inside the main shaft to and has connected to it a flexible strap, chain, or cable F, which passes around the spiral drum or sheave G, which is rigid with the winding-drum A. It will now be understood that when the armature is attracted to the poles of the magnet the upper end of the long arm E of the armature-lever is thrown inward and the flexible strap F is unwound from the spiral drum or sheave G, rotating the latter and the winding-drum A, coiling the spring B, and rotating the ratchet-wheel A under the pawl, by which it is retained after the attraction of the magnet, for the armature ceases ,by reason of the interruption of the current, and through which the energy in the spring is transmitted to the prime-wheel A and the clockmovement actuated until the mainspring is uncoiled and the spiral sheave and drum restored to their original position, during which movement the armature is withdrawn from the magnet-poles ready to be reattracted thereto when the magnet is next energized.

The spiral sheave G and its relation to the other parts constitute one feature of my invention. To understand its purpose and effect, it should be considered that the attraction experienced by the armature when the magnet is energized at the most remote position of the armature must be sufficient to start the armature from the rest, and also that the force experienced by the armature will increase rapidly as it approaches the poles. In order to utilize all the energy thus developed,the connections from the armature to the train to be actuated by its movement should be such as to cause the work done at each point or through each increment of the arm atures movement to be substantially proportioned to the energy developed from inerement to increment-that is to say, the resistance to the pull of the armature, due to its connection with the winding mechanism, should be least at the commencement, both because at that point the attractive force of the magnet must overcome the inertia of the armature, starting it from the position of rest, and also because at that point the armature is most remote from the magnet and experiences the least of its attractive force. As the armature approaches the attractive poles, the work done may increase quite rapidly, and at the last increment of movement the work may be very much greater than at the first equal increment. These relations I aim to produce by the connections and relative positions of the parts described. In the first place, the movement of the armature-lever at the commencement of the approach of the armature to the poles causes the strap F to pull on the sheave G at the extremity of its greatest ra dius, so that it acts with the longest leverage on the sh aft a, and this leverage diminishes as the armature continues to move toward the magnet until at the finish of a long pull the leverage may be less than half what it was at the commencement, an d the work done by the movement of the armature through an equal angle will be therefore about twice what it was at the commencement. The rate of increase may be varied as dictated by experience with any given form of magnet and armature and a spring of any given size and stiffness, since, obviously, the increasing resistance of the spring as it is coiled must be taken into account. Furthermore, the direction of the pull of the armature-lever on the spiral sheave changes as the armature approaches the mag net-poles, the change being such as to increase the work done, for it will be noticed that when the armature is most remote from the poles the strap F runs from the end of the arm E of the armaturelever in a direction nearly at right angles to a tangent to the periphery of the sheave at that point, so that as the lever swings inward the amount of strap unwound from the sheave is small relatively to the amount of movement of the end of the lever attached to the strap; but as the movement continues the pole becomes more nearly tangential, until at some point the peripheral movement of the sheave at the point where the strap runs. off from it is equal to the movement of the end of the lever, and thereafter this continues to be the factthat is to say, the strap thereafter pulls off the sheave in a direction tangential to the sheave at the last point of contact. The relation of the end of the lever to the sheave when the armature is at its most remote position being as described is especially favorable to the starting of the armature from a position of rest, because scarcely any work beyond moving the armature and its lever is done at the starting. If it were desired to carry this feature to the extreme, it will be evident that it would be only necessary to extend the spiral sheave far enough so that when the armature is at its most remote position the point of the sheave would be in line with the connection of the strap to the lever and the fulcrum of the latter. It is not necessary to carry the principle to this extreme in order to get an effective action; but this explanation will enable any mechanic to adapt the structure to the particular circumstances of each case.

I will now describe the contact making and breaking device. On the main shaft a, behind the she-ave G and rigid with said sheave, I mount two disks or collars H and K, respectively, the former of metal and the latter of non-conductingmaterial, as vuloanite or hard rubber. Each of these disks or collars is cut away on the side which faces the other to form a shoulder, a small segment of'the are of the collar H being cut away and a notch being cut in the collar K h represents this shoulder 011 the metal collar H, and 7c the corresponding shoulder on the hard-rubber collar K. These two collars are rigidly connected together, their shoulders not coinciding, but set apart circumferentially about the shaft,

so that between them on the circumference there is measured an angle observable on Fig. 5 and indicated by-the lines a; y and y .2, making the angle at 1 z, which I term the windin g-angle, for this is the angle through which the winding-drum is rotated by the pull of the armaturerlever in the action above described.

L is a spring, one end of which is set into the insulating-block D and is bound therein by the screw-post D setting against it and making it thereby part of the metallic circuit, through which the magnet is energized. T iis spring is coiled, so that its end L, which extends down outside the shaft (0, and the guardflange K of the disk K tends not only to press inward toward the shaft, but also tends to spring. in rearward against the hard-rubber disk K} Now the shoulder It of the disk K is inclined toward the shoulder h of the disk H, as seen at 7c. Assuming, therefore, that the end of the spring at a given position of the parts rests upon the circular periphery of the collar K and against its guard-flange K, the rotation of said disk with the train brings the end of the spring to the commencement of the shoulder 7c. The tension of the spring tending to force it inward toward the shaft to will cause it toslide down the incline 75 of the shoulder and lodge upon the shoulder 72, thus making a contact which completes the electric circuit and energizes the magnet. The action of the armature, caused by the att 'active energy of the magnet, now rotates the collars H and K, with the winding-drum, in the opposite direction from that in which they were rotating when the contact was produced, and the end of the spring slides on the segmentshoulder h until that shoulder is revolved y from under it and it rests upon the circular periphery of the collar, whereupon its lateral tendency causes it to fly over against the guide-flange K of the insulatin g-collar K and to rest wholly upon that collar, thus breaking the circuit and de-energiz'ing the magnet. It will be manifest now that the duration of the metallic contact by which the electric circuit is maintained corresponds to the rotation of the collars, winding drum, and sheave G through the angle 50 y] This angle will therefore be made to correspond to the movement of the armature from its most remote position to its position of contact with the magnetpoles, and thereby the electrical energy will be continued throughout and only throughout the movement of the armature which it produces, so that no waste of electrical energy will be suffered.

In order that the angle through which the spring is in contact with the collar may be adjusted to agree with the winding-angle, I secure the two collars II and K adj ustably to each other by means of the screw 71 which passes through the arc slot 76, and which, being slackened, permits the collars to be moved about the shaft to set their shoulders apart whatever distance is necessary. In. order to adjust the spring Ii so that it will operate accurately, as designed in connection with the collars, I secure the insulating-block I) to the frame in a similar way-that is, by screws (Z passing through arc slots (Z in the frame-so that the slot may be tilted slightly to bring the point of the spring to its proper position for producing the action described.

I claim- 1. In an electric winding device, in combination with the electro-magnet, its energizing circuit and its armature; a lever which can ries the armature; the main spring; a spiral sheave suitably connected to the main spring to wind it up when properly rotated; a flexible strap, chain or cable connected to the armature lever and running thence about the spiral sheave and secured thereto: substantially as set forth.

2. In an electric winding device, in combination with the electro-magnet, its energizing circuit and its armature; the lever which carries such armature; the main spring; the sheave suitably connected to the main spring to wind it up when properly rotated; a flexible strap, chain or cable connected to the armature lever and running thence onto the sheave and secured to the latter; the fulcrum of the lever, the point of departure of the strap therefrom, and the point of contact of the strap with the sheave being approximately in a straight line when the armature is at the starting point of its movement toward the magnet: substantially as and for the purpose set forth.

In an electric winding device, in combination with the electro-magnet, its energizing circuit and its armature; the leverwhich carries the armature; the main spring; a spiral sheave suitably connected to the main spring to wind it up when properly located; the flexible strap, chain or cable connected to the lever and running thence onto the sheave and secured to the latter; the line of the strap from the lever to the sheave at the starting point of the armatures movement toward the magnet, making an angle with a tangent to the sheave at the point of contact of the strap therewith: substantially as set forth.

4:. In an electric winding device, in combination with the main spring, winding drum, shaft or barrel, the electro-magnet and its armature and connections therefrom to said winding drum, shaft or barrel, by which the movement of the armature when the magnet is energized effects the winding; the metallic collar H, and the insulating collar K located rigidly with respect to each other in immediate juxtaposition on the same shaft; a spring finger in the magnet circuit adapted to be lodged upon either of the collars, the metallic collar having the shoulder h and the insulating collar having the shoulder 7a; the distance between the commencement of said shoulders measured on the circumference of the insulating collar corresponding to the angular winding movement of the main spring shaft, drum or barrel; the spring having a sidewise tendency toward the insulating collar and a radial tendency toward the shaft, and the insulating collar having the incline 71 beyond its shoulder 10, adapted to guide the spring contrary to its sidewise tendency onto the metallic collar: substantially as set forth.

5. In an electric winding device, in combination with the main spring and its winding drum, shaft or barrel, and its energizing circuit and its armature, and connections from the armature to the winding drum, shaft or barrel; whereby the movement of the armature toward the magnet tends. to wind up the main spring; the contact making and breakin g device in the circuit comprising a metallic and an insulating collar in immediate juxtaposition on the same shaft and rigidly connected the spring finger adapted to bear upon the periphery of one or the other of said collars as the shaft revolves, the conformation of the periphery of the collars being adapted to cause the spring to oscillate laterally from one collar to the other at the limits of a cer tain angular movement of the collars about their axes: substantially as set forth.

6. In an electric winding device, in combination with the main spring, winding drum, shaft 01 barrel, the electro-magnet and its armature and connections therefronr to said winding drum, shaft or barrel, by which the movement of the armature when the magnet is energized effects the Winding; the metallic collar H, and the insulating collar K located rigidly With respect to each other in immediate juxtaposition on the same shaft; a spring finger in the magnet circuit adapted to be lodged upon either of the collars, the metallic collar having the shoulder 7b and the insulating collar having the shoulderk; the distance between the commencement of said shoulders measured on the circumference of the insulating collar corresponding to the angular winding movement of the main spring shaft, drum or barrel; the spring having a sidewise tendency toward the shaft, and the insulating collar having the incline 7c beyond its 

